1. Field of the Invention
This invention relates to mechanical apparatus for deterring birds from landing at undesirable locations.
2. Prior Art
Because of the noises they can make, and the mess they can leave behind, birds are not always welcomed. Private as well as public areas can be rendered unsightly and unusable because birds have chosen a nearby overhead position as a favorite perch. The nuisance created by the birds can also be unhealthy as diseases carried in fungi in bird droppings can be communicated to humans. These problems and others can affect the small private residence as well as the large corporate skyscrapers, and every type, size and shape structure inbetween.
In some areas, the pigeon is the primary offending bird. Along the coastlines, seagulls are most troublesome. In other areas, starlings, sparrows, swallows and blackbirds are most often the problem, although there are countless species that can be the culprit.
For these reasons, numerous methods and devices have been utilized and devised to keep birds away. Mock predators, such as owls, hawks or snakes have been erected. Some of these have been quite sophisticated, built to move periodically and to emit sound. But the birds usually quickly discover the ruse, and return, actually perching on their mortal enemy model.
Others have resorted to real-life predators, using peregrin falcons, for example, to disburse pigeons. These real predators, however, are expensive, indiscriminate, unreliable and largely ineffective.
Others have attempted to use a noise deterrence, omitting a reoccurring sharp report to scare the birds away. This, too, is only minimally effective, as the birds become quickly accustomed to the noise. Further, this method is not useful around humans, as the sound is as noisome to them as to the birds.
Other devices and methods which have been employed to combat the bird problem include a gel which is applied to the perch area, giving the bird a chemical hot-foot when it lands in the goo. Ultrasound emitters designed to irritate the birds are also available. These all have drawbacks. The chemical gel is sticky, and therefore dust, dirt and small objects adhere to it, making it unsightly. Also it loses its effectiveness over time. The ultrasound emitters are expensive, need a power source, and are of only limited effectiveness in open areas.
The most utilized prior art device comprises a continuous metal spine from which protrude a repetitive pattern of points prongs. This device is affixed by screws or nails to those areas where the birds would unwantedly perch. Any bird with the temerity to attempt to land on this device painfully realizes his folly.
While this device has proven effective, it is subject to several drawbacks. First, it can be injurious to the birds, as bloodied feet and impaled wings are not unusual. Second, it is potentially injurious to humans who unexpectedly come into contact with it. Third, it is relatively expensive. Fourth, it is somewhat unsightly and harsh in appearance. Fifth, papers and leaves can become impaled upon its tines, creating an eyesore.
Lastly, some people have even resulted to the ultimate sanction, actually killing large numbers of the offending birds in an attempt to frighten them off. This, of course, is highly disfavored as a deterrence means, but it is indicative of the levels of frustration experienced when an area goes literally "to the birds".
This led the inventor to develop a coiled wire device for deterring birds. (See application Ser. No. 076,896, filed July 23, 1987, allowed but not yet issued). Therein, a coiled wire is attached directly to the perch location. A need has arisen, however, for a pre-assembled unit in which the coil spacing is predetermined.